JPH11160640A - Manufacture of scanning optical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a scanning optical device capable of smoothly adjusting a laser beam diameter, extending ranges for adhesives and light sources, and preventing deviation caused by heat and impact. SOLUTION: A collimator assembly part 21 is formed by interposing a collimator lens 2 between a 1st holder 4a and a 2nd holder 4b, and then, a photo- curable adhesive 23 is applied on the surface 22 of a scanning optical device before the assembly part 21 is mounted thereon, and after adjusting a laser beam diameter, the collimator assembly part 21 is fixedly bonded by emitting light beams by a light beam device 24. The facing surface 4c and the mount surface 4d of a holder 4 are formed of a light transmission member.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical unit used in an apparatus for recording an image by scanning a laser beam modulated by an image signal on a photosensitive drum, and an optical unit such as an optical disk using a semiconductor laser. The present invention relates to a method for manufacturing a scanning optical device such as a pickup unit of a dynamic information recording and reproducing device.

[0002]

2. Description of the Related Art Conventionally, there is a laser beam printer which scans a laser beam to record an image. As shown in FIG. 5, a laser scanning device uses a beam from a semiconductor laser 11 modulated by an image signal as shown in FIG. Is collimated by a collimator lens 12, passes through a cylindrical lens 13, is deflected by a deflector 15, is imaged on a photosensitive drum 17 by an imaging lens system 16, and is scanned. Conventionally, the semiconductor laser 11, the collimating lens 12, the cylindrical lens 13, the deflector 1
5. The lens system 16 is unitized as a scanning optical device.

In the conventional scanning optical device, when the collimating lens 12 and the cylindrical lens 13 are fixed to the scanning optical device, the collimating lens 12 and the cylindrical lens 13 are mounted on a frame, and they are operated to operate the laser beam. After adjusting the diameter, an adhesive is often applied to the side surface and fixed.

[0004]

However, the conventional fixing method of the collimating lens 12 and the cylindrical lens 13 has the following problems.

(1) When adjusting the laser beam diameter by operating the collimating lens 12 and the cylindrical lens 13, friction occurs between the mounting surface on the frame side and it is difficult to operate smoothly.

(2) The collimating lens 12 and the cylindrical lens 13 are made of a transparent resin. However, when a light-curable adhesive is used, the type of the adhesive and the light source used are limited.

(3) Since the area of the side surfaces of the collimating lens 12 and the cylindrical lens 13 is small, the bonding area is small, and it is shifted by heat or impact.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and includes a semiconductor laser as a light source, at least a mounting surface and a surface opposing the mounting surface being a light-transmitting member. A holder is used to hold the lens, a light-curing adhesive is applied to one surface of the housing of the scanning optical device or the mounting surface of the holder, and the holder is placed on the optical path of the emitted light of the semiconductor laser. This is a method of manufacturing a scanning optical device for irradiating light from a surface to cure a light-curable adhesive and fix a holder.

[0009]

Embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1 which is a schematic cross-sectional view, the scanning optical device includes a laser module 5a including a semiconductor laser, a collimating lens, a cylindrical lens, and the like, a polygon mirror 5b, and an fθ lens 5c. Image information is formed on the photosensitive drum 9 from above through the second reflection mirror 5e and the third reflection mirror 5f.

FIG. 2 is a view showing a laser module 5a. A semiconductor laser bracket 1a for fixing the semiconductor laser 1, a collimating lens 2 for converting incident light into a parallel light beam, a holder 4 for fixing the collimating lens 2, Cylindrical lens 3 for focusing only the vertical direction of the light beam
These are fixed on a scanning optical device. The holder 4 is composed of a first holder 4a and a second holder 4b, and at least a mounting surface on the scanning optical device and a surface facing the mounting surface are formed of a light transmitting member.

FIG. 3 is a view showing a method of fixing the holder 4. As shown in FIG. 3 (a), a collimator assembly is formed by interposing a collimator lens 2 between a first holder 4a and a second holder 4b. 3B, the mounting surface 4d of the assembly 21 and the scanning optical device surface 2 are formed as shown in FIG.
2, a light-curing adhesive 23 is applied, the holder 4 is placed on the optical path of the emitted light of the semiconductor laser, and the holder 4 is operated to adjust the laser beam diameter. And the light beam is transmitted from the opposing surface 4c to the mounting surface 4d to cure the light-curable adhesive 23 and fix the collimated assembly 21. In this embodiment,
Although the case where the holder 4 is provided on the collimating lens 2 has been described, the same configuration can be applied to the case of the cylindrical lens 3, the case where the collimating lens 2 and the cylindrical lens 3 are integrated, and the case of other lenses. Also,
UV-curable adhesive, which is a light-curable adhesive, is 300-
At 380 nm, the visible light curable adhesive is 300-500
When irradiated in the nm range, it can be cured.

As in this embodiment, the mounting surface 4d of the holder 4 on the scanning optical device and the opposing surface 4c are formed of a light transmitting member, and light is irradiated from the opposing surface 4c to mount the mounting surface 4d.
When the holder 4 is operated to adjust the laser beam diameter in order to cure the light-curable adhesive 23 applied to d and fix the holder 4, the light-curable adhesive 23 has not been cured yet. Easy to adjust by acting as a lubricant,
In addition, the surface tension of the light-curing adhesive 23 makes it difficult for deviation such as inclination to occur. After curing, the contact area of the holder 4 with the scanning optical device surface 22 is large, so that the fixing is stable.

As the light transmitting member, plastic (PMMA) or the like may be used. In this case, the wavelength to be transmitted is limited, and it has a property of having a spectral characteristic that it is not transmitted even when irradiated with ultraviolet rays. Therefore, when the holder 4 is fixed, the light-curable adhesive may be cured with a high-pressure mercury lamp having a main wavelength of 405 nm. In addition, even in the case of ultraviolet irradiation (300 to 380 nm), if the irradiation is performed at 365 nm, which has the highest emission spectral energy in the range, the power is greatly reduced, but the energy (heat amount) must be secured by the irradiation time. It can be cured because a light beam of about 400 nm is irradiated.

As shown in FIG. 4 (a), if the viscosity of the light-curable adhesive is small, there is no surface tension. Since it is difficult to control the amount and stringing occurs, 1,000 to 20,000 CPS is desirable. Then, as shown in FIG. 4B, if the applied amount of the light-curable adhesive is small, the adhesive strength is inferior because the applied area is small, and if the applied amount is large, the light-outgoing adhesive sticks out to the lens surface. The optical axis shift due to the change of the mounting height due to the thickness of the adhesive occurs.
1 g is desirable. It should be noted that the double circles in FIG. 4 are evaluations that are optimal for use, が is suitable for use, Δ is usable, and X is not usable.

[0015]

As described above, according to the present invention,
A manufacturing method in which the mounting surface of the holder on the scanning optical device and its opposing surface are formed of a light transmitting member, and the holder is fixed with a light-curable adhesive, enables a smooth operation when adjusting the laser beam diameter. It is possible to provide a scanning optical device in which the type of the adhesive and the width of the light source to be used are widened and the displacement due to heat or impact is prevented.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a scanning optical device of the present invention.

FIG. 2 is a diagram showing a partially enlarged view of FIG. 1;

FIG. 3 is a view showing a fixing method of the present invention.

FIG. 4 is a diagram showing an experimental example of the present invention.

FIG. 5 is a diagram showing a conventional scanning optical device.

[Explanation of symbols]

 1, 11: semiconductor laser 1a: semiconductor laser bracket 2, 12: collimating lens 3, 13: cylindrical lens 4: holder 4a: first holder 4b: second holder 4c: facing surface 4d: mounting surface 5a: laser Module 5b: polygon mirror 5c: fθ lens 5d, 5e, 5f: reflection mirror 9, 17: photosensitive drum 15: deflector 16: lens system 21: collimating assembly 22: scanning optical device surface 23: light-curing adhesive 24: Light beam device

Claims (2)

[Claims] A semiconductor laser serving as a light source is provided, and at least a mounting surface and a surface facing the mounting surface hold a lens in a holder which is a light-transmitting member. A light-curing adhesive is applied to the mounting surface of the holder, and after the holder is mounted on the optical path of the emitted light of the semiconductor laser, light is irradiated from the facing surface to apply the light-curing adhesive. A method for manufacturing a scanning optical device, wherein the holder is fixed by hardening. 2. The apparatus according to claim 1, wherein said lens is a collimating lens and / or
The method according to claim 1, wherein the scanning optical device is a cylindrical lens.